Settings: Minimal refactor to support new dreams api.

Fix breaking changes to the dreams api.  Master toggle
and multiple dreams support in Settings will be done in
a subsequent change.

Bug:7028665
Change-Id: Ia56dd00ec50323fbba06473b1747e5015a3f1898

src/com/android/settings/DreamTesterPreference.java

@@ -36,7 +36,10 @@ public class DreamTesterPreference extends Preference {
     protected void onClick() {
         IDreamManager dm = IDreamManager.Stub.asInterface(ServiceManager.getService("dreams"));
         try {
-            ComponentName cn = dm.getDreamComponent();
+            ComponentName[] dreams = dm.getDreamComponents();
+            if (dreams == null || dreams.length == 0)
+                return;
+            ComponentName cn = dreams[0];
             Log.v(TAG, "DreamComponent cn=" + cn);
             dm.testDream(cn);
         } catch (RemoteException ex) {